PRP vs. Hyaluronic Acid for Knee Pain: Which Works Better?

meta-analysis PMID: 32912243

Quick Summary: A review of multiple studies found that platelet-rich plasma (PRP) injections may be better than hyaluronic acid (HA) injections for relieving knee pain and improving function in people with osteoarthritis.

What The Research Found

This research looked at many studies comparing two common treatments for knee osteoarthritis: PRP injections and hyaluronic acid (HA) injections. The results showed that PRP injections seemed to work better than HA injections for:

Reducing pain: People who got PRP reported less pain at 6 and 12 months after the injections.

Improving knee function: PRP helped people move their knees better at 1, 3, 6, and 12 months.

Study Details

Who was studied: People with knee osteoarthritis.

How long: The studies followed people for up to 12 months.

What they took: Participants received either PRP injections or HA injections directly into their knee joint.

What This Means For You

If you have knee osteoarthritis, this research suggests that PRP injections might be a better option than HA injections for pain relief and improved knee function. However, it's important to talk to your doctor about the best treatment for your specific situation. They can help you weigh the pros and cons of each treatment option.

Study Limitations

The studies used different methods for giving the injections, which could affect the results.

The research only looked at the effects for up to a year, so we don't know how long the benefits last.

The study didn't include all the studies ever done on this topic.

Key Findings

This meta-analysis found that platelet-rich plasma (PRP) injections provided superior pain relief compared to hyaluronic acid (HA) injections at 6 and 12 months post-treatment, as measured by WOMAC pain scores (p < 0.05) and VAS scores. PRP also showed better functional recovery at all time points (1, 3, 6, and 12 months) via WOMAC function scores, with statistically significant differences (p < 0.05). WOMAC total scores and IKDC scores favored PRP at 6 months and 3/6 months, respectively. No significant differences were observed in Lequesne Index, KOOS scores, or adverse events between groups. EQ-VAS scores indicated lower quality-of-life improvements in the PRP group at 12 months.

Study Design

This was a systematic review and meta-analysis of 20 randomized controlled trials (RCTs) published in English before January 23, 2020. Data sources included PubMed, Embase, Web of Science, and the Cochrane Library. The analysis focused on clinical outcomes for knee osteoarthritis (KOA) patients treated with PRP or HA injections. Follow-up periods ranged from 1 to 12 months. Statistical pooling used Stata 12.0 software, but specific sample sizes for individual trials or aggregated data were not detailed in the provided summary.

Dosage & Administration

The study evaluated intra-articular injections of PRP and HA. However, the summary did not specify dosages, preparation methods (e.g., PRP concentration protocols), or injection frequencies used across the included trials. Variability in these parameters among the 20 RCTs may have influenced outcomes.

Results & Efficacy

Pain Relief: PRP reduced pain more effectively than HA at 6 and 12 months (WOMAC pain scores and VAS scores; p < 0.05).
Function: WOMAC function scores showed significant improvements in PRP-treated patients at all follow-up intervals (1, 3, 6, and 12 months; p < 0.05).
Total Symptom Scores: WOMAC total scores favored PRP at 6 and 12 months.
IKDC Scores: PRP improved knee function significantly at 3 and 6 months (p < 0.05).
Quality of Life: EQ-VAS scores were lower in the PRP group at 12 months, suggesting less improvement in general health status.
Safety: Adverse events were comparable between PRP and HA groups (no p-values or confidence intervals reported).

Limitations

Heterogeneity: The analysis pooled diverse RCTs with unspecified variations in PRP/HA dosing, preparation, and injection protocols.
Short-Term Focus: Most trials had follow-up periods ≤12 months, limiting insights into long-term (>1 year) efficacy.
Outcome Variability: No significant differences were found for KOOS or Lequesne Index scores, highlighting inconsistent functional metrics.
Publication Bias: The study excluded non-English trials, potentially skewing results.
Lack of Demographics: Patient age, severity of OA, or baseline characteristics were not detailed in the summary.

Clinical Relevance

For KOA patients, PRP injections may offer greater pain relief and functional improvement than HA in the short-to-medium term (≤12 months). However, the lack of standardized dosing and long-term data necessitates caution. HA remains a viable option for those seeking comparable safety and quality-of-life outcomes. Clinicians should consider individual patient factors and consult specific trial protocols for dosing guidance. Future research should address optimal PRP formulation and extended follow-up to confirm durability.

Note: This analysis is limited to the summary provided; full study access may reveal additional details on effect sizes, confidence intervals, and adverse event rates.